Remove seal.lib.hadut

The hadut module has been superceded by pydoop.hadut and other modules
provided by pydoop.  It only presents a liability and would need to be
updated to work with Hadoop 2
Remove unused imports
Bring back seal.lib.hadut, in light form

The hadoop utilities module in Pydoop does not provide the functionality
for an easy migration.  This commit bring back the seal.lib.hadut module
but without the redundant functionality.
Use logger properly